Oregon Revised Statutes Occupations and Professions § 697.045

(1) A registered collection agency has a property right in any claim or account assigned to the agency in writing for collection. Except as may be otherwise provided in writing between the assignor of the claim or account and the registered collection agency, the registered collection agency as assignee of the claim or account, in its own name, may:

(2) Except as may be otherwise provided in writing between the assignor of the claim or account and the registered collection agency, the assignor may withdraw the claim or account from the agency at any time without condition or charge.

(3) Notwithstanding ORS 9.160 and 9.320, in any action in the small claims department of a circuit court or justice court a registered collection agency may appear as a party without appearance by attorney for the purpose of recovering the amount owing on a claim or account assigned to the agency in writing for collection. The provisions of this subsection apply to any supplementary proceeding in aid of execution after entry of a judgment in the small claims department.

(4) No collection agency is entitled to bring or maintain an action involving the collection of a claim or account on behalf of its customers in any courts of this state without alleging and proving that it is duly registered under ORS 697.015 and 697.031. A registration certificate or a certification of registration by the Director of the Department of Consumer and Business Services for any designated time period shall be received by the court as prima facie evidence of the collection agency's registration for the time period designated.